The Grey's writers would never miss a chance to take advantage of airing on the year's spookiest night, and, based on the promo for the episode, they've gone all out. We're talking zombies. Yes, zombies. Or at least a patient with some sort of zombie-like disease.

What kind of scary fun can we expect next week? We've taken a closer look at the promo to see what secrets it reveals.

Cristina is not pro trick or treating. Of course she's not. We love her to death, but as Owen vents, she's "no fun sometimes."

Who's Arizona talking to? At :04we see Arizona in bed, saying "tonight's Halloween." Do you think she's talking to Leah?

Zombies? At :08 we see a thrashing, flailing patient who looks more than a little zombified. "Zombie?!" Leah says in shock. At :11 April tells the patient that "zombies aren't real." Seems like he thinks he might have been bitten by a zombie, if nothing else.

Leah’s hurt. It's a little hard to tell, but we think Leah is having something pulled out of her shoulder at :05. Does she get hurt? At :12, it looks like the "zombie" bites her. That can't be good. Even though we doubt this guy's the legit walking dead, he might have an infection. Also, being bitten hurts!

Happy Cristina. "I have wanted to see this since med school," Cristina gushes. Is she talking about the zombie dude, or someone else? Either way, we love it when Cristina gets all excited about medicine.

Check it out for yourself here.

Did we miss anything? Interpret something wrong? Sound off in the comments below.